March 22, 2017 – by Bob Henson in the Wunderblog of Weather Underground.com
Each day of every year, a quiet disaster unfolds in households and hospitals across the world. More than 10,000 lives are lost worldwide every 24 hours as a direct or indirect consequence of poor air quality. Bad air takes its toll quietly, with no need for the oversized drama of a hurricane or tornado. Sometimes air quality becomes so dangerous that it can’t be ignored. Much of the time, though, dangerous air goes about its dirty work with little attention from policymakers and the public.
The World Health Organization (WHO) has dubbed air pollution “the world’s largest single environmental health risk.” It is high time we treated the life-threatening aspects of dirty air, and the life-sustaining properties of a clean atmosphere, with the full appreciation they ought to have.
Figure 1. Los Angeles, CA, shrouded in late-afternoon smog as viewed from the Hollywood Hills. Griffith Observatory is at far left. Image credit: Diliff/Wikimedia Commons
Here at Weather Underground, we are taking steps in this direction by bringing air quality sensors into our 250,000-strong network of personal weather stations. We believe there is great power in being able to measure the quality of the air in one’s own neighborhood and to share that information with the world at large.
We are also ramping up our coverage of air pollution issues here at Category 6. Along with occasional guest authors, Jeff Masters and I will be exploring the many facets of air quality, including its effects on people and ecosystems and how it intersects with both weather and climate. For example, Jeff will soon be posting an overview of the health hazards posed by poor air quality. This topic was highlighted on March 6 by a distressing report from the World Health Organization: Each year, respiratory infections linked to indoor and outdoor air pollution and second-hand smoke take the lives of some 570,000 children under the age of 5. That’s roughly 10% of all deaths in that age group each year.
Figure 2. Schoolchildren in Delhi, India, wore masks as schools re-opened on November 10, 2016, after three days of closure due to severe smog. Image credit: Sajjad Hussain/AFP/Getty Images.
For both children and adults, the air indoors can be just as dangerous as the air outdoors. Each year more than 4 million people die prematurely as a consequence of household air pollution—largely the result of inefficient, smoke-belching cookstoves that are used routinely in developing nations. This toll is even higher than the WHO’s estimate of 3 million premature deaths a year from outdoor air pollution.
Even the most pristine places can be touched by the global spread of air pollution. In Antarctica, scientists have found traces of lead trapped within ice cores. Using isotopes (variations in the number of neutrons within an element), researchers were able to track the heavy-metal pollution to industrial activity in Australia as far back as the late 1800s.
Today, as much as 25% of the sulfate and mercury pollution along the U.S. West Coast comes from emissions from coal-fired power plants in China. These pollutants take just five to eight days to cross the Pacific on the prevailing upper-level westerly winds.
Figure 3. Motorcyclists ride through thick smog on January 9, 2017, in Zhengzhou, China. The nation’s Central Meteorological Observatory issued a yellow alert for smog in Zhengzhou on Sunday night, January 8. Visibility dropped below 50 meters (160 feet) in parts of the city on Monday morning. Image credit: VCG/VCG via Getty Images.